JP2699666B2 - Deodorizing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deodorizing apparatus for adsorbing and collecting malodorous components and decomposing and removing them by using a combination of ozone and a catalyst.

[0002]

2. Description of the Related Art In recent years, odor pollution has been widely taken up as a social problem, and various new odor control techniques have been developed and implemented.

Conventionally, deodorization has been carried out by a chemical cleaning method, an adsorption method, a direct combustion method, a catalytic combustion method, an oxidation method using ozone, etc., each of which has advantages and disadvantages, and has many practical problems. For example, the above-described oxidation method using ozone is a method of treating malodorous components by using the strong oxidation action of ozone, and can be treated even at a low temperature of about room temperature, so that the running cost is lower than the other methods described above. It is. However, there is a disadvantage that a long reactor is required because the reaction between the ozone and the malodorous component in the gas phase is slow, and secondary pollution by ozone occurs because unreacted ozone is discharged.

Two methods have been proposed as methods for compensating for the above-mentioned disadvantages. The first method is a method of deodorizing with an apparatus having an ozone generator and an ozone decomposition filter (Japanese Patent Application Laid-Open No. 61-29358).

In this method, unreacted ozone is decomposed and then exhausted, so that there is no fear of secondary pollution. However, it is necessary to increase the capacity of the reactor to decompose ozone and malodorous components in the gas phase. Alternatively, when the capacity of the reactor is small, the processing gas passes through the ozone decomposition filter before being sufficiently deodorized, and has a disadvantage that the deodorizing effect is reduced.

The second method uses a catalyst for the purpose of contacting and reacting ozone with a malodorous component to promote an oxidation reaction and also to catalytically decompose unreacted ozone. As a catalyst used in this method, a catalyst in which a metal oxide is supported on a carrier made of a carbonaceous material (Japanese Patent Application Laid-Open No.
No. 19371) and a catalyst in which a metal oxide is supported on an activated alumina carrier (JP-A-53-30908). However, any of the catalysts has a high ozone decomposing ability, so that a large amount of ozone is required to obtain a desired deodorizing effect.

[0007]

As described above, in the prior art, a catalyst having a high ozone resolving power, which adsorbs and collects malodorous components and simultaneously decomposes ozone, is used.
For this reason, in order to obtain a sufficient deodorizing effect, the consumption of ozone is increased, and it is also difficult to substantially eliminate the emission of unreacted ozone.

[0008] It is an object of the present invention to provide a deodorizing apparatus capable of reducing ozone consumption and obtaining a sufficient deodorizing effect.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a deodorizing apparatus for adsorbing and collecting malodorous components by means of a combination of ozone and a catalyst to decompose and remove the malodorous components. A deodorizing device comprising an adsorbing layer of a hydrophobic zeolite to adsorb and a catalyst layer for decomposing excess ozone.

The present invention is also characterized in that the adsorption layer and the catalyst layer have a honeycomb structure in the deodorizing apparatus of the first aspect.

[0011]

According to the present invention, first, a large amount of offensive odor components can be adsorbed and collected, and the odorous components are oxidized and decomposed while coming into contact with ozone by using an adsorption layer which does not easily decompose ozone, thereby eliminating odor.
Next, excess ozone is decomposed and made harmless through a catalyst layer that decomposes ozone.

In order to improve the effect of oxidative decomposition of ozone and malodorous components, it is preferable that the adsorbing layer is made of a material which adsorbs as much malodorous components as possible and which does not decompose ozone as much as possible.

In general, it is well known that zeolite is an excellent adsorbent for polar odors such as ammonia, amine and mercaptan. However, zeolite has a large amount of adsorbed moisture, and when used in the air, the influence of moisture hinders the adsorption and collection of malodorous components, and the amount of adsorbed zeolite often decreases in practical use.

On the other hand, the hydrophobic zeolite used in the adsorption layer of the present invention (indicated by reference numeral 1 in FIG. 1) is chemically a crystal of an aluminosilicate metal salt, and has oxygen atoms in its silica structure. Has almost no basicity,
Does not participate in hydrogen bond formation. For this reason, the Si—O—Si bond on the zeolite surface exhibits water repellency and does not adsorb water molecules. Further, since the strong adsorbing power to polar substances depends on the electrostatic force of the cation corresponding to the number of aluminum atoms in the skeleton, Al ₂ O ₃ in the crystal is reduced, and SiO ₂ / Al ₂ O ₃
When is increased, the water repellency increases and the amount of adsorbed moisture can be reduced.

As shown in FIG. 2, the amount of water adsorbed is SiO ₂
/ Al ₂ O ₃ decreases from around 20, and when it is 80 or more, almost no water is adsorbed. On the other hand, the adsorption amounts of ammonia, amine and mercaptan having polar odors are SiO ₂ / Al ₂ O
_{When 3} is in the range of 20 to 80, it is large, and particularly preferably in the range of 40 to 60.

Further, the hydrophobic zeolite has a property of adsorbing and trapping a large amount of malodorous components as an adsorbent, and at the same time, does not greatly affect the decomposition of ozone.

In terms of adsorption efficiency, the structure of the hydrophobic zeolite described above is a honeycomb (honeycomb) as shown in FIG.
The structure is preferred.

The catalyst layer of the present invention (reference numeral 2 in FIG. 1)
As a catalyst for decomposing excess ozone used in the above, an ordinary ozone decomposition catalyst is used. For example, a conventional binary oxide composed of titanium and silicon (hereinafter referred to as T
A catalyst composed of iO ₂ —SiO ₂ ) and β-type manganese dioxide (hereinafter abbreviated as MnO ₂ ) may be used. In addition, TiO ₂ —SiO ₂ and MnO
₂ may be impregnated and carried. In any case, it is preferable to have a honeycomb (honeycomb) structure.

The above-mentioned adsorption layer and catalyst layer may be integrated, or may be provided separately.

Using the adsorption layer and the catalyst layer as described above,
Decomposing the malodorous components can significantly reduce ozone consumption, as shown in the examples below.

[0021]

EXAMPLE In an air at 20 ° C. and 60% room humidity, 0.2
The polar odor dimethylamine having a concentration of mg / m ³ was subjected to a deodorizing treatment using the conventional apparatus and the present invention, and the results were compared. In the prior art, for example, in the case of direct treatment using a manganese catalyst, the amount of ozone consumed for treatment until the odor becomes undetectable (0.1 PPM or less) is 0.8 mg / m 2.
^{Was 3} .

On the other hand, when deodorization was carried out with the apparatus of the present invention under the same conditions, the ozone consumption was 0.3 mg / m ³ .

As is clear from the results of the above comparative experiments, according to the present invention, the amount of ozone consumed for oxidatively decomposing malodorous components can be reduced.

[0024]

According to the present invention, a sufficient deodorizing effect can be obtained by the adsorption layer and the catalyst layer absorbing and collecting malodorous components and decomposing excess harmful ozone, respectively. In addition, since unreacted ozone is decomposed and then exhausted, there is no need to worry about secondary pollution, and the ozone consumption can be particularly reduced.

[Brief description of the drawings]

FIG. 1 is a simplified perspective view of a deodorizing device according to the present invention.

FIG. 2 Amount of water adsorbed on SiO ₂ / Al ₂ O _{3 of} a hydrophobic zeolite and bad odor (10 p at 20 ° C., 60% room humidity)
4 is a graph showing the amount of pm ammonia adsorbed.

[Explanation of symbols]

 1 adsorption layer 2 catalyst layer

Claims (2)

(57) [Claims] 1. A deodorizing device for adsorbing and collecting malodorous components and decomposing and removing them by a combination of ozone and a catalyst.
The deodorizing apparatus is characterized in that the deodorizing apparatus includes a hydrophobic zeolite adsorption layer that is less likely to decompose ozone and adsorbs malodorous components, and a catalyst layer that decomposes excess ozone. 2. The deodorizing apparatus according to claim 1, wherein the adsorption layer and the catalyst layer have a honeycomb structure.